Darren Kocs1, A Mark Fendrick. 1. Divisions of Hematology/Oncology, Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor 48109-0429, USA.
Abstract
BACKGROUND: While the off-label use of oncology interventions is widespread, the factors influencing off-label use and the resultant influence on oncology drug expenditures are not well understood. STUDY DESIGN: To assess the indications for rituximab use, a retrospective review was undertaken at a single academic center between September 1998 and June 2001. METHODS: Patient diagnoses were linked to pharmacy records, and each administration of rituximab was classified as either on-label or off-label as defined by FDA-approved indications. The resultant utilization patterns were the foundation for a conceptual model designed to identify factors that influence off-label use of oncology-related therapeutics and forecast the effect of off-label use on aggregate oncology drug expenditures. RESULTS: One hundred one patients received a total of 428 rituximab administrations during the study period. Most (320, 75%) of the administrations were for off-label indications. Although the extent of off-label and on-label use grew at a similar rate initially, off-label utilization increased nearly exponentially over time as on-label uses lessened. A conceptual model that describes factors that promote, inhibit, or have a mixed influence on off-label use may help predict future patterns of off-label utilization and allow better forecasting of oncology drug expenditures. CONCLUSIONS: The off-label use of rituximab is substantial. Projections of oncology-related patterns of care and drug expenditures must account for the potential for off-label use.
BACKGROUND: While the off-label use of oncology interventions is widespread, the factors influencing off-label use and the resultant influence on oncology drug expenditures are not well understood. STUDY DESIGN: To assess the indications for rituximab use, a retrospective review was undertaken at a single academic center between September 1998 and June 2001. METHODS:Patient diagnoses were linked to pharmacy records, and each administration of rituximab was classified as either on-label or off-label as defined by FDA-approved indications. The resultant utilization patterns were the foundation for a conceptual model designed to identify factors that influence off-label use of oncology-related therapeutics and forecast the effect of off-label use on aggregate oncology drug expenditures. RESULTS: One hundred one patients received a total of 428 rituximab administrations during the study period. Most (320, 75%) of the administrations were for off-label indications. Although the extent of off-label and on-label use grew at a similar rate initially, off-label utilization increased nearly exponentially over time as on-label uses lessened. A conceptual model that describes factors that promote, inhibit, or have a mixed influence on off-label use may help predict future patterns of off-label utilization and allow better forecasting of oncology drug expenditures. CONCLUSIONS: The off-label use of rituximab is substantial. Projections of oncology-related patterns of care and drug expenditures must account for the potential for off-label use.
Authors: Jason D Wright; Alfred I Neugut; Elizabeth T Wilde; Donna L Buono; Jennifer Malin; Wei Y Tsai; Dawn L Hershman Journal: J Clin Oncol Date: 2011-08-01 Impact factor: 44.544